Tagged Questions

A database structure that can improve the speed of queries at the cost of disk space and slower inserts/updates. It stores a copy of one or more columns but structures the data differently to allow for faster access.

I have a table in Oracle 10.2g that I'm trying to import roughly 11 million rows into. The table contains an SDO_GEOMETRY column. It previously had NOT NULL constraints on all 3 columns, a primary key ...

I can not use alter table () on my stored procedure i don't have a permission to do that in the big database data_pro.
How can i use index in my stored procedure for my 2 fields in where condition?
...

I have a trigger applied to a table to write inserts and updates to a history table. That history table can grow pretty fast, and we want to see, if we can speed up insert operation a bit.
The values ...

I want to check if our code does use only indexed columns.
I think it does, but I want to be sure.
How can I configure/modify PostgreSQL to raise an exception if it needs to do an sequence scan?
It ...

It is said that to optimize the query cost of execution, then it would be by indexing the field of tables in database.
Since I don't have a permission to enter the phpmyadmin in my web server as I am ...

I have a collection which has 50 million records in it.
After using wired Tiger its size became only 3 GB (2 GB data 700 MB index).
I have created index on this collection.
But when i do a range query ...

I have a table, which has two columns say A and B as part of the Primary index PI_AB.
I have to alter the length of B column - increase it.
I was planning to alter the primary index to just have A, ...

I am using Mongo Replica set and it seems to be working fine but when i check db.serverStatus i saw that there are lots of accessesNotInMemory for all The DBs in my mongo instance.
I checked MY RAM ...

I'm new to PostgreSQL. I'm currently working on an open source software package which is java based using postgresql 9.3.
For some requirement I populated a table (organisationunit) without using the ...

We had dropped a unique constraint using the ALTER TABLE DROP CONSTRAINT script, but it is still throwing the Unique Constraint exception while trying to insert. We drilled this down to two possible ...

I have a statement that selects from two tables news and status. It seems that the index on the column status of the table news is not used.
This table has about 70.000 rows and the query costs too ...

If my table only has two columns (username, groupname) and a million or so rows, will an index improve performance at all? Wouldn't it take just as long to search the index file as it would to search ...

We have a table with 350m rows and 12 columns, and around 1m rows adding everyday. We have crappy hardware and we cannot add an index on one of the 12 columns that we really really need to. (severe ...

I have a SQL 2008 Standard server on full mirror (safety). I reorganize all indexes weekly. I am looking into rebuilding a few indexes to improve performance. I ran DBCC SHOWCONTIG on my largest, most ...

I'd like to get a count(*) from a relatively small joined table (returned result is about ~30000 rows). I use Postgresql 9.3 so simply getting select count(*) from tasks_task; uses index-only scan, ...

I have two tables, table A which contains date and name of table B entry and table B which contains its name and type. Table a has a composite index on table_b_name and date. I'm selecting all table A ...